Pump



W. N. sMlTH I 2,021,156

PUMP

Filed Nov. l0, 1933 2 Sheets-Sheet 2 E FW @0j l l 11ml@ 5 u 1 M INVENTOR Has' ATTORNEYS.

Patented Nov. 19, 1935 UNITED sTATEs PATENT OFFICE PUMP William Neil Smith, Douglaston, N. Y. Application November 1o, 1933, serial No. 697,420

6 Claims.

tween the relatively sliding elements thereof.,

These pumps therefore are preferably driven by a source of power which is of such character as to enable rapid movement of the movable pump element to take place in order that the individual pumping strokes may take place with a minimum lliI loss of iiuid from the pumping chamber.

In order that a pump may be provided having a chamber from which no uuid can escape, the present invention has been designed and an object thereof is to provide a pump by means of which fluid may be supplied under pressure without loss of fluid or pressure from the pumping chamber.

A further object of the invention is to provide a fluid pump having means forming a fluid tight chamber, the volume of which may be varied by a suitable power source.

A further object of the invention is to provide a fluid pump having a bellows forming a pumping chamber and provided with means to actuate the bellows, the mechanism further being provided with bellows guiding and displacement members of such character as to enable substantially the entire contents of the bellows to be discharged during the pumping operation.

A further object of the invention is toprovide an improved bellows pump of the double acting type wherein fluid is supplied under an initial pressure to the bellows or pumping chamber wherein further pressure is applied thereto.

Further objects, not specifically enumerated above, will be apparent as the invention is described in connection with the accompanying drawings, wherein:

Figure 1 is a view in section, taken through the axis of a pump constructed in accordance with the present invention and showing the bellows moved into an expanded position wherein the pumping chamber is of maximum volume.

Figure 2 is a View similar to Figure l, showing the bellows moved into a collapsed or exhausted position at which time the contents haveibeen.

discharged from the pump.

Figure 3 is a view similar to Figure l, sho-wing a bellows pump of the double acting type` constructed in accordance with the present invention.

Figure 4 is a view in section, taken on line 4-4 of Figure 3, and looking in the direction of the arrows. 5

Figure 5 is a View in section, taken on line 5-5 of Figure 3, and looking in the direction of the arrows.

Referring to the constructionshown in Figures l and 2, thepump is shown as being formed with 1o.

a cylindrical guide or housing Ii) having a cover II secured thereto in which a plunger I2 is-slidably received. This plunger may be actuated by any suitable source of power and is secured to a movable head I3 which is slidably mounted withlo in the guide It. A stationary head I4 is secured to the opposite end of the guide i@ by means of screws I5 or other suitable mechanism and is formed with a hollow cylindrical central portion I6 within which a guide shaft I'I is received as 2O will be described hereinafter. Between the movable and stationary heads I3 and I4 a flexible bellows I8 is secured, the bellows preferably being formed of rubber. The ends of the bellows are anchored to the heads by inserting the extrem- 25 ities thereof in a reentrant fashion into serrated annular grooves I9, the sectional annular wedge rings 20 being forced into the reentrant portions of the extremities of the bellows to force such portions against the adjacent serrated portions 30 of the grooves in the heads.

To serve as a further sealing means between the heads and the ends of the bellows the adja` cent sides of the heads are formed with annular recesses 2l into which the adjacent portions of 35 the bellows are forced by means of clamping rings 22 which may be split or otherwisee formed and suitably secured over the grooves 2| in order that the material of the bellows may be forced thereinto. Y 40 The bellows may be formed with a plurality of folds depending upon the volume desired for the pumping chamber and these folds are guided by means of outer positioning rings 23 and inner positioning discs 24. If desired, either or both of the discs and rings may be secured tothe bellows at proper intervals, in the present construction, the inner discs being shown as secured thereto by annular clamping members 25 which are fo-rmed with inner ribs 26 which are adapted 50 to force the material of the bellows into peripheral groovesZl, formed in the discs 24. Each of the discs 24 is preferably splined to the guide Il by a key 28 which is adapted to engage a cooperating limiting stop 29, formed in the guide 55` Y provided with a key 33 which is The slots for each ofthe respective keys 28 are of sufficient length to permit the several discs 24 to be moved along the guide |'I until each of the discs is properly spaced when the bellows is moved toV the expanded position as shown in Figure 1. YIn like fashion, each of the guide rings 23 is adapted to engage a cooperating limiting slot 3 i, formed in the housing or guide IIJ. In this fashion, the position of the rings 23 is properly maintained under all ccnditions of operation. Y

Apertures 32 and 33 are formed in the housing I0 and 35 are formed in the rings 23 and discs 24, respectively. 'Ihese apertures prevent the exist- Y ence of undesirable pressure regions between portions of the tion.

A suitable air inlet is provided at 36 and includes a one way valve 37| which permits air to be drawn into the bellows chamber through the duct and guideway I6 while preventing theflow of air or otherV fluid in the opposite direction. A safety valve 39, communicating through duct 43 with the guideway I6, prevents the accumulation of a predetermined excessive pressure within the bellows chamber, the iluid being discharged from the pump through a suitable outlet 4| which, lin the accompanying drawings, is shown as communicating with a reservoir 42 through a one way valve 43. l

pump mechanism during opera- In order that valves 33 and 43 may not stick and thus impair the Voperation of the mechanism, the valve stems of the said valves are formed with extensions 38'which areadapted to be engaged positively by the endof` the' plunger I1. In the construction shown the end of the plunger is provided with anV enlarged flange 38 and. a foot 38 which engage the extensions 38 and thus prevent the valves from sticking. f

The elements are assembled drawingsjand the bellows thus ble fluid tight chamber, all of the contents of as shown .in the which may be exhausted therefrom inasmuch as rthe discs 24 are formed of such size and shape as to occupy the entire interior of the bellows when it is moved to a collapsed position, as shown n ,Figure 2.

If desired, the discs 24 may be of less diameter than the maximum diameter of the bellows or the discs may be of full diameter inasmuch as the bellows is made of a flexible material, such as rubber.

In the construction shown in Figures 3, 4, and 5, the invention has been embodied in a double acting sitioning and displacement discs and rings which are secured to the bellows, also as previously described. 'IVhe cylindrical guide |33 is imperforate and the cover IIH thereof provided with one or more intake valves |02. As described in connection with the construction shown in Figures l and 2V, a safety valve 39 is provided as well' asa discharge duct 4|. The plunger shaft isshown at |03 and is connected to the movable head in a suitable Vfashion in order that the movable head may serve as a positive means to compress the fluid between the cover I0! `and the upper side of the movable head. The connection between the plunger guide |03 andthe stationary head |D| is rendered fluid tight by a` rubber -gstocking H14 which is-secured. between the adjacent serrated surfaces of a flange |35 formed` on a cap |06 and the surface of the cover IUI. The flange |05 is and cover II, respectively, while apertures 34 Y provides a variaone way valve means to admit secured to the'cover by means of screws |01 and wedge ring |68 which forces` the adjacent end of Y the stocking |04 into the serrated peripheral groove |39 formed in the upper extremity of the guide |33. A serrated cap II is secured to the guide |33 by means of a screw I and a threaded extension I 2 of the cap I |0 has secured thereto a power plunger H3. A cap ||4` on the housing li slidably receives a plunger 3. The edges of the cap III? are slotted at ||5 to permit air to 1 pass by the cap while the edges of the ring |08 ,are slotted at H6 for a similar purpose.

Theluid which is compressed within the chamber above the movablehead is forced into a duct |I"|' in the` guide |63 which communicates with a fittingV IIB and a duct ||9 which leads into the chamber formed by the expanded bellows. A

one wayvalve I 2|]` is provided in the inlet connec-V tion to prevent the back ilow of iuidand the first stage of the compressing operation thus cmexpanded bellows. Movement of the head in the Vopposite direction draws air into the first corn--V .Y prises the forcing of fluid from the chamber above the movable head into the'chamber formed by the tionally compresses the air within the second compression chamber formed by the contracting bellows.

The fitting ||8 is received within a guide |2| which is secured to the movable head, the duct i I3 being formed in this last named guide. The end of the guide |2| is formed with a foot |22 which is adapted to engage the valve 4| to prevent sticking thereof, as previously described. I

From the foregoing, itwill be seen that'a pump has been provided which functions fully regardless of theV speed of operation thereof inasmuch as leakage from the compression chamber or chambers thereof does not take place. The pump is further characterized by relativelyrfewmoving parts and the parts which do move do not require particularly accurate machining operations for the manufacture thereof. Moreover, theducts and valve between the several compression chambers are of simple and improved construction.

While the invention has been described with specific reference to the accompanying'drawings, itis not to be limited, save as defined in the appended claims. Y I claim as my invention: j 1. A pump comprising an extensible tractible fluid tight chamber forming' means, means to actuate the chamber forming means, fluid into the chamber, a separate one way Valve means to receive fluid from the chamber, air displacement and guiding means within the chamber to ll substantially the Vspace therein when the chamber lforming means is in contracted position, and means to guide and limit displacement means. Y

2. A pump comprising an extensible and contractible fluid tight chamber forming means, means to actuate the chamber forming means, one wayY valve means to admit fluid into the chamber, a separate one way valve means to receive fluid from the chamber, air and guiding means within the chamber to fill-substantially the-space therein whenthe chamber forming means is contracted position, means to guide and limit the movement of the 'displacement means, guide means for the exterior of Ythe chamber forming means, and means to guide and and condisplacementV the movement of the limit movement of the last named guide means.

3. A pump comprising a cylindrical housing, an extensible and contractible fluid tight chamcer forming means in the housing, one Way valve means to admit uid into the chamber, a separate one Way Valve means to` receive fluid from the chamber, air displacement means within the chamber to fill substantially the space therein when the chamber forming means is in contracted position, a guide shaft within the chamber upon which the displacement means is mounted, and annular -guide means within the housing and exterior to the chamber forming means.

4. A pump comprising an extensible and contractible fluid tight chamber forming means, a stationary head secured to one end of the chamber forming means, a movable head secured to the other end thereof, peripheral grooves formed in the heads and Wedge rings to force the ends of the chamber forming means into the grooves.

5. A pump comprising a cylindrical housing, an extensible and oontractible fluid tight rubber chamber forming means in the housing, a stationary head secured to one end of the chamber forming means, a movable head secured to the other end thereof, peripheral grooves formed in `the heads, Wedge rings to force the ends of the chamber forming means into the grooves and interior and exterior guide and displacement means in the housing cooperating with the chamber forming means.

6. A pump comp-rising an extensible and contractible fluid tight chamber forming means, means to actuate the chamber forming means, one Way valve means to admit fluid into the chamber, a separate one Way valve to receive uid from the chamber, and means operated by the chamber 'orm'mg actuating means to prevent certain of the valves from sticking.

WILLIAM NEIL SMITH. 

